Development of Strategies for the Synthesis of Heterocycles and Carbocycles; and Investigation of Chemistry Course Placement on Undergraduate Students

[摘要] Heterocycles and carbocycles are important motifs in synthetic chemistry as they are present in many natural products and pharmaceuticals and possess biological activities. Among other uses, cyclic and bicyclic urea motifs are found in HIV protease inhibitors, and can be used as chiral auxiliaries in organic synthesis. Indanes and indane derivatives are CNS stimulants and possess, among others, anti-inflammatory, antiviral, and anti-cancer properties.Chapter 2 of this thesis describes a new method for the synthesis of cyclic and bicyclic ureas via a new ruthenium-catalyzed cross-metathesis/aza-Michael reaction strategy. This method provides access to functionalized bicyclic ureas with stereochemical patterns that are not easily accessible with other methods. The cyclic and bicyclic urea products were synthesized with this method in moderate to good yield and up to >20:1 dr.In recent years, the Wolfe group has examined the synthesis of carbocycles using palladium-catalyzed alkene difunctionalization reactions. These methods have been developed to synthesize amino-substituted carbocycles, alkoxy-substituted carbocycles, and alkyl-substituted carbocycles using alkene-tethered triflates and exogenous nucleophiles. Chapter 3 of this thesis describes the pursuit of the use of internal alkenes and carbon-based nucleophiles to synthesize alkyl-substituted carbocycles. Carbocycles were synthesized in moderate to good yields and in excellent diastereoselectivity.The remaining chapters of this thesis describe efforts toward chemical education research examining placement experiences of undergraduate students at the University of Michigan. Chapter 4 examines the factors that students consider when making their decision about which course to take first in the chemistry sequence. Students tend to consider their perceived preparedness and the university recommendation when making their decision.Chapter 5 of this thesis examines the effect of student decision-making on their experience in the subsequent courses. Students were asked about their perceived preparedness for their current chemistry course and also the perceived cost of their decision. Students tend to have felt more prepared for their current course if they were recommended for a course that was above what they enrolled into. Also students felt there were positive and negative consequences of their decision, and although for the most part students felt they made the right decision, but some reflected on effort costs including loss of valued alternatives, emotional cost, and task effort cost.

[发布机构] University of Michigan

[效力级别] chemistry education research

[关键词] synthetic organic chemistry;chemistry education research;Chemistry;Science;Chemistry